Choke-feed lubricator.



Patented Dec. l6, I902.

G. S. WEBSTER.

CHOKE FEED LUBRICATOR.

(Application filed Aug. 8, 1902.

(No Model.)

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PATENT OFFICE.

GEORGE S.- WEBSTER, OF MINNEAPOLIS, MINNESOTA.

CHOKE-FEED LUBRICATOR.

SPECIFICATION forming part of Letters Patent No. 715,913, dated December 16, 1902.

Application filed August 8, 1902.

4'0 all whom it may concern:

Be it known that I, GEORGE S. WnBsTER, a citizen of the United States, residing at Minneapolis, in the county of Hennepin and State of Minnesota, have invented certain new and usefullmprovementsin Choke-Feed Lubricators; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

My invention has for its objectto provide an improvement in automatic choke-feed devices for lubricators such as used for lubricating the cylinders of a locomotive; and to this end it consists of the novel devices and combinationsofdeviceshereinafterdescribed, and defined in the claims.

As is a well-known fact, in lubricators of the above character the oil in the lubricator cup or reservoir is subject to the steam-pressure from the boiler and is fed into the cylinders against the back pressure, which varies greatly with respect to the boiler-pressure, but is always materially less. \Vhen this back pressure is greatly reduced or rendered negligible in effectas, for instance,

when the throttle-valve is nearly or 'quite closeda very small or restricted oilpassage will suffice to supply the desired amount of oil. When, however, this back pressure is high, reaching, say, one-half or more of the boiler-pressure, as when the throttle-valve is wide open, a much freer or less restricted passage for the supply of oil must be afforded in order to give the proper supply of oil to the cylinders. The principal feature of my inven-. tion is directed to improved means for automatically regulating this variable choke-feed.

Another feature of my invention is directed to an improved device for preventing the escape of steam in case the sight-tube of the lu bricator should be broken.

The invention is illustrated in the accompa-- nying drawings, wherein like characters indicate like parts throughout the several views.

Figure 1 is a view principally in side elevation, but with some parts broken away and others sectioned,showing an automatic chokefeed lubricator embodying the several features of my invention; and Figs. 2 and 3 are sections on the line m of Fig. '1, showing Serial No. 118,861. (No model.)

different positions of the difierential pistonvalve.

The numeral 1 indicates the closed oil cupor reservoir, shown as provided at its top with a dome 2, into the end of which steampressure from the boiler is delivered through a screw threaded nipple 3, by means of a pipe. (Not shown.) For the purposes of this case the internal construction of the reservoir 1 and dome 2 need not be considered, as they are of standard construction and well understood to all persons familiar with this class of mechanism. The oil under boiler-pressure is fed out from the bottom of the reservoir 1 into an elbow 4, which-is preferably equipped with a feed-valve 5 6 of the character shown and claimed in my prior patent, No. 656,616, of August 21, 1900, which valve controls the discharge of the oil from an upturned nozzle 7. From the nozzle 7 the oil is delivered into the lower end of a vertical sight-tube 8, the upper end of which leads into the depending neck 9 of an elbow-like valve case or housing 10, which is suitably supported from the reservoir 1. I

Into the laterally-projecting portion of the case or housing 10 is screw-threaded or otherwise secured a sleeve-like valve-seat, herein designated as a choke-plug 11. To the inner end of the plug 11 is secured, preferably by screw-threaded engagement, a cap 12.

The numerals 13 and 14 indicate a differential piston-valve, the large member 13 of which works in the seat 15, formed within the plug 11, and the small member 14 of which works through a seat or perforation 16 in the cap 12. The said differential piston-valve is preferably provided with a flanged extension 17, which works in a cylindrical guide-passage 18 of the plug 11. The passage 18 extends from the seat and leads to a slightly-contracted passage 19 in the outer end of the plug 11. The passage 19 is in communication, through suitable connections, (not shown,) with the steam-chests of the engine. A-pl'urality of by-passages open radially through the sides of the plug opposite to the piston-seat 15. When the differential piston stands in the position indicated in Fig. 2, the by-passages .are closed, but when it stands as shown in Fig. 3 the said by-passages will be opened. It should be here noted that the by-passages 20 are in free communication with the interior of the case or housing 10 through a clearance-passage 21, which surrounds the inner end of the plug 11. A restricted or capillary oil-duct 22 extends axially through the dif ferential piston 13 and 14 and its flanged extension 17.

To the top of the case or housing 10 is secured an ordinary open oil-cup 23, which is normally closed at its bottom by a valve 24 and is provided with a hollow depending stem 25, to the lower end of which is secured a valve 26. The valve 26 is provided with an axial oil-duct 27, which opens into the hollow stem 25. Normally the valve 26 closes the upper end of the depending sleeve 9, except for the passage 27. Said passage 27 is normally closed by a ball-valve 28, which, however, will freely rise to permit oil to pass upward. The hollow stem 25 is provided with lateral openings 29, through which the oil finds ready escape from the interior thereof into the case or housing 10. These openings 29, it will be noted, are in horizontal line with the axial openings 22 of the differential piston-valve, so that the water-line will be approximately as indicated by the dotted line marked IV L in Fig. 1.

The operation of the device will be substantially as follows: Suppose, for instance, the boiler-pressure to be one hundred and fifty pounds and the back pressure from the steam-chest to be materiallyless than seventyfive. In this case the excessive pressure on the small member 14 of the differential piston will force the said piston-valve into the position indicated in Fig. 2, thereby closing the by-passages 20 and leaving open for the supply of oil only. the axial passage 22 of said piston-valve. This, as is evident, will give a restricted supply of oil. On the other hand, suppose the boiler-pressure to remain one hundred and fifty pounds and the pressure in the steam-chest to exceed seventy-five pounds. In this case the back pressure on the larger member of the difierential piston will force said piston into the position indicated in Fig. 3, thereby opening up the by-passages 20 and giving much freer or less restricted supply of oil to the steam-chests, and hence to the cylinders. The by-passages 20, together with the axial passage 22, should give an aggregate conducting capacity approximately equal to that of the outlet-passage 19, although this close relation is not absolutely necessary. \Vhen the valve 26 is raised and removed from the casing 10, together with the cup 23 and its connections, (which cup is detachably connected to said housing 10 by a screwthreaded union 30,) the sight-tube 8 may be removed vertically from working position or placed in working position by passing the same through the said casing 10. The ballvalve 28 does not interfere with the proper feed of the oil upward through the water contained in the sight-tube and sleeve 9 into the interior of the casing 10; but, as already indicated, it always stands ready to prevent the blowing off of steam from the casing 10 should the sight-tube 8 be accidentally broken.

From what has already been said it will be understood that my invention is capable of considerable modification within the scope of the claims presented.

I have tested the practicability of the device by actual usage of the same on a locomotive and the same has proven highly satisfactory for the purposes had in view.

What I claim, and desire to secure by Letters Patent of the United States, is as follows:

1. In an automatic choke-feed lubrieator, the combination with a piston-valve seat having two bores of different size, of a differential piston working therein and provided with a restricted oil-supply duct, the small and large members of said piston being respectively, subject to lubricator and cylinder or back pressure, said valve-seat having by-passages adapted to be opened and closed by said piston and affording a freer passage for the oil when the back pressure increases to a certain extent, substantially as described.

2. In anautomatic choke-feed lubricator, the combination with a valve-casing and a choke-plug projecting into the same with clearance around its inner end, of aditferential piston-valve working within said chokeplug and provided with a restricted oil-supplying duct extending from end to end thereof, the smaller and larger members of the piston-valve being subject, respectively, to lubricator and cylinder or back pressure, and the said choke-plughaving radial by-passages at its inner end and adapted to be opened and closed by the large member of said piston-valve and affording a freer passage of the oil when the back pressure is increased to a certain extent, substantially as described.

3. In an automatic choke-feed lubricator, the combination with a valve casing or housing 10, of a detachable choke-plug 11 having the seat 15 and guide-passage 18 communieating with the same, by-passages 20 in the said seat adjacent to said passage, and outletpassage 19 beyond said passage 18, the cap 12 applied at the inner end of said seat 15 and having the seat 16, and the differential piston-valve 13 14 working in the seats 15 16 and provided with the axial oil-duet 22, and the flange extension 20, the latter of which works in said passage 18, the larger member 13 of said piston-valve serving to open and close said by-passages 20, said parts operating substantially as described.

In testimony whereof I aifix my signature in presence of two witnesses.

GEORGE S. WEBSTER.

Witnesses:

ELIZABETH H. KELIHER, F. D. MERCHANT. 

